it all depends on the potential of the coins that I hold because not all coins have a good future, but I prefer holding long-term coins that have the potential to grow in price in the future.
the best time to sell it, in my opinion, is when the price of the coin has reached higher than when the price we get it, so we will be able to get a profit, but need to remember in doing our trade do not be too ambitious to get big profits, better profit but can continue rather than once get a big profit and then lose money in the future.
Many analysts say that most altcoin will lose its relevance in the near future. The fact is that most have no final product and therefore they have no prospects. Based on this information, you can realistically assume that it is better to sell altcoins now than to lose your money in the future. But if you are 100% sure of your altcoin, then you need to keep them at all costs.
If you trust the team you can hold and wait, the only way to see what future will bring to you, there's no assurance as there's a lots of different opinions but trusting your own knowledge will allow you hold and wait, it's all about your capabilities to calmly wait till things happen according to your plans.